1. Technical Field
The present technical field relates to acceleration sensors for use in, for example, vehicles.
2. Background Art
FIG. 12 is a cross-sectional view of conventional acceleration sensor 1. Acceleration sensor 1 includes weight part 2, outer frame 5, strain part 4, upper substrate 8, self-check electrode 7, and opposed electrode 6. Strain part 4 has a first end connected to weight part 2 and a second end connected to outer frame 5. Upper substrate 8 is connected to outer frame 5 so as to face weight part 2. Self-check electrode 7 is formed on the upper surface of weight part 2. Opposed electrode 6 is disposed on upper substrate 8 at a location facing self-check electrode 7.
In this configuration, when a voltage is applied across self-check electrode 7 and opposed electrode 6 so as to apply an electrostatic voltage V to weight part 2, weight part 2 operates as if acceleration is applied to weight part 2. Based on this operation, it can be self-checked whether acceleration sensor 1 normally operates or not.